There has been known a structure in which a seat lock mechanism is connected to a key cylinder by a cable, the key cylinder being adapted to lock and unlock the seat lock mechanism by a key operation, and a guard body for preventing access to a cable is provided to a bracket supporting the key cylinder (for example, see Patent Literature 1).
Also, there has been known a structure formed so that a rear center cover covers a seat lock mechanism to guard the seat lock mechanism (for example, see Patent Literature 2).